I know that Nickel is used as catalysts in Hydrogenating of vegetable oil. If copper is present in the process, what will happen? On the periodic table nickel and copper are near one another.
Where are you located? If you have access to a Sales rep from one of the major catalyst manfacturers, I'm sure he can find out for you. Typically, catalyst manufacturers have been asked about similar problems and have developed catalysts that are resistant to poisoning by particular trace metals.
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